LONDON — An American infertility clinic seeking business in Britain prompted fierce criticism by offering free eggs from a U.S. woman to one participant in a promotional seminar in London on Wednesday.

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The event has sparked a debate in Britain about the ethics of an event that many said violated the spirit, if not the letter, of a European Union law forbidding fertile women from being paid for their eggs.

Eggs donors in the U.K. cannot be compensated for more than 250 pounds ($384) per month for travel and time off work.

The rule limits the number of donors and makes it very difficult for infertile women to obtain eggs in the U.K. and much of Europe.

It is not illegal for Europeans to pay for eggs overseas, and for years infertile European women seeking eggs have traveled to other countries like America — where paying for eggs and sperm is common and legal.

As part of a marketing push in the U.K., the Virginia-based Genetics and IVF Institute held a free seminar for about 100 British attendants on Wednesday night, where one randomly chosen couple won a free donor egg treatment.

To donate, a woman must undergo a monthlong treatment that involves injecting herself with hormones to stimulate the ovaries and then undergoing a procedure to retrieve several eggs.

The clinic’s prize is worth more than $10,000 — a $6,000 fee for the donor and $4000 in medical costs associated with the hormone treatment and egg retrieval.

Other U.S. clinics have been known to pay women up to $35,000 for their eggs.

The Genetics and IVF Institute said its donors were college-educated women between 19 and 32. It has been giving away eggs in similar promotions in the U.S. for more than a year.

Because the winner of Wednesday’s lottery would travel to the U.S. to get eggs from a U.S. donor, the company’s paying for them does not break any British laws.

But British fertility experts slammed the event as a publicity stunt.

“There’s something shocking in the association of a raffle and giving away a human product,” said Dr. Francoise Shenfield, a fertility and medical ethics expert at University College London. “In Europe, we have the general idea that altruism is a good thing, and we don’t want to turn human body parts into a commodity.”

Shenfield, who has studied Europeans going abroad for fertility treatment, said it was impossible to know how many Britons were going to the U.S., since they do not have to report it.

Britain’s Human Fertilisation and Embryology Authority, which regulates fertility treatment, said the U.S. clinic’s raffle was inappropriate.

“It trivializes altruistic donation” and runs contrary to regulations “to protect the dignity of donors and recipients,” the agency said.

The Genetics and IVF Institute, based in Fairfax, Virginia, countered that it was simply offering a seminar in London commonly held in the U.S.

“They’re not raffling off a human egg,” company spokeswoman Trina Leonard said.

Britain’s fertility laws stem from the EU’s Tissues and Cells Directive, which says donors can only be paid for their inconvenience, though the compensation cost varies across the continent. In Spain, for example, women can receive up to about euro900 (about $1,200) for donating eggs.

Fertility expert Allan Pacey, at the University of Sheffield, suggested Britain’s supply of available eggs would increase if women were offered more money to donate, saying “250 pounds barely scratches the surface” of covering for the inconvenience.

Pacey drew a line, however, at selling the eggs, and said the U.S. clinic’s stunt risked turning human eggs into a commodity. “Having a lottery is not how we do things in this country,” he said.

Polish citizen Hanna Tlatlik, who works in a London shop, said she thought paying for eggs was a good idea, as it would allow more women to have children. “You have to pay for everything,” said Tlatlik, 24. “What can I give if not money?”

But not all women in Britain thought offering more money for eggs was a good idea.

“It doesn’t feel like a commodity that should be profitable. I could never charge someone for that,” said Rhiannon Prytherch, a 28-year-old actress and theater manager in central English city of Derby. She said she might feel differently, though, if she were the one needing eggs. “If I were a woman who wanted to have a child, I would be willing to pay.”

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